Improvement in process of forming vacuum in freezing apparatus



UNITED STATES PATENT CFFICE.

EDWARD S. BOYNTON, OF MERIDEN, CONNECTICUT, ASSIGNOR TO HIMSELF AND CHARLES PARKER, OF SAME PLACE.

IMPROVEMENT IN PROCESS 0F FORMING VACUUM IN FREEZING APPARATUS.l

Specification forming part of Letters Patent No. 106,251, dated August 9, 1870.

To all whom 'it may concern:

Be it known that I, EDWARD S. BoYNToN,

of Meriden, in the county of New Haven and State of Connecticut, have invented a new Improvement in Process l'or Forming Vacuum in Freezing Apparatus; and I do hereby declare the following, when taken in connection with the accompanying drawing and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawing constitutes part of this specification, and represents a sectional view ot' an apparatus in which my process is introduced.

,This invention relates to an improvement in the process for forming the vacuum in apparatus for making ice.

Heretofore this has been donc by exhausting the air from the vacuum-chamber.

In practice it is found impossible to produce a perfect vacuum, inasmuch as the eX- hausting-pump, at each stroke, takes only a certain number of inches of the contentsthat is to say, supposing the vacuum-chamber to be the capacity of one hundred and the pump one, each stroke of the pump would remove one per cent. of the contents of the chamber; but as the air expands as fast as any portion is removed, it follows that it is impossible to form even a theoretical vacuum by puin ping.

rlhe devices which have heretofore been used have been of an extensive and complicated character, necessitating a large outlay in making the freezing apparatus, which, by my invention is almost entirely avoided, and the vacuum is theoretically perfect; and it consists in forming the vacuum in freezing apparatus by filling the vacuum-chamber with a liquid and removing the said liquid by force or gravitation.

In order to illustrate my invention, I will show it as applied to a freezing apparatus.

A and B are two vacuum-chambers, by preference in such relative 4position to each other that a pump, C, may be connected to both by respective tubes A and B', each iitted with stop-cocks.

- D D are the freezing-baths, arranged outside the vacuum-chambers, and are filled with brine 0r other non-congealing liquid, by preference brine.

E E are ether-receivers, from which a number of tubes, a, extend up through theY baths D D and turn into the vacuum-chambers at or near the top. The said chambers also communicate into the ether-receivers through tubes d, each provided with a stop-cock.

One of the chambers-say A-is lled with a liquid which will not con geal, as alcohol, &c., and the receiver E supplied with ether. The pump is then started, drawing the liquid from the chamber A, and forcing it into the chamber B until the liquid is removed from one chamber and transferred to the other, thus forming, theoretically, a perfect vacuum, as the pump will at each stroke remove the same quantity of liquid until all is removed. The ether, in consequence of the vacuum passing up through the tubes, is vaporized into the vacuum chamber, which so far reduces the temperature of the freezing liquid in the baths D D that Water, in suitable vessels immersed in the said baths, will quickly congeal; then, when the full effects of the iirst vacuum have been attained, reverse the pump, open the stop-cock from the vacumn-chamber to the ether-receiver, and the iniowing liquid condenses the ether, which iows directly back into its receiver, and a vacuum is formed in the second chamber, causing the circulation of the ether, as before described.

To condense the ether and cause it to return to the receiver, air may be forced in the receiver instead of the liquid; then, when the ether has all returned to the receiver, the vacuum may be again filled with liquid, and this process I prefer.

A single vacuum is all that is necessary', and this may be entirely surrounded by the freezing-bath, and, instead of a pump to draw out the liquid to form tl1evacuun1,the chamber may be set so high (thirty-two feet) that the liquid will run out by its own gravitation, and thus produce the vacuum without any apparatus.

I claim- The herein-described process of forming the vacuum in freezing apparatus, which consists in filling the vacuum-chamber with a liquid, then removing the same therefrom by gravitation or otherwise, substantially as set forth.

' EDVARD S. BOYN'ION.

Witnesses:

W. F. PARKER, ANDW. G. LOWERN.` 

